I've come up with a little project to hopefully improve upon my nitrous system. I have an idea that I feel aught to be doable but there's a few things I'm not familiar enough with. I'm gonna try to be as concise as I can.
I'm using a Harris Speed Works "the interface" controller to give me the fueling for nitrous through the maf signal. It works brilliantly but it's lacking one feature that I'd like to try to integrate and that is compensation for bottle pressure since it decreases during a run and makes me progressively richer and thus slower as I go down the strip.
One feature of this controller (that I do not use or ever intend to use for it's intended purpose is the rpm-based enrichment function which taps into your rpm lead and richens the result maf adjustment up to a preset amount. The manual for the controller says it will adjust up to 8000rpm and can be set as high as 15%. Based off my rough calculations, 15% is enough to give me bottle pressure fueling compensation for a range of about 150psi which would help with the degrading pressure issue while I'm spraying. More would be nice but that's enough for the trouble I think.
So the controller is looking for an rpm signal - I want to take a standard 0-5v nitrous pressure sender and digitally translate that into a made-up rpm signal. I'm figuring I'd need some kind of programmable micro-controller/programmable IC type deal to input the voltage and give me an rpm signal and then tune the ranges such that it works for my nitrous controller. I don't know exactly what my controller does as far as the relation between rpm and the preset fuel adjustment percentage but I could test and figure that out by plotting its output vs rpm after I have a way to do that.
So where I'm left with some questions is does anyone know exactly what the rpm lead for my nitrous controller is looking for from an electrical standpoint? In other words, I don't really know what an rpm or tach signal is in this case (it's meant for an LS1,LS2,etc btw). Secondly, I'm not as much of a geek as I wish I was - what can I use to do this whole digital I/O conversion?
If anyone has any other totally different ideas about how I could accomplish this blast away!
This is what rpm signal sources the controller uses by the way
I'm using a Harris Speed Works "the interface" controller to give me the fueling for nitrous through the maf signal. It works brilliantly but it's lacking one feature that I'd like to try to integrate and that is compensation for bottle pressure since it decreases during a run and makes me progressively richer and thus slower as I go down the strip.
One feature of this controller (that I do not use or ever intend to use for it's intended purpose is the rpm-based enrichment function which taps into your rpm lead and richens the result maf adjustment up to a preset amount. The manual for the controller says it will adjust up to 8000rpm and can be set as high as 15%. Based off my rough calculations, 15% is enough to give me bottle pressure fueling compensation for a range of about 150psi which would help with the degrading pressure issue while I'm spraying. More would be nice but that's enough for the trouble I think.
So the controller is looking for an rpm signal - I want to take a standard 0-5v nitrous pressure sender and digitally translate that into a made-up rpm signal. I'm figuring I'd need some kind of programmable micro-controller/programmable IC type deal to input the voltage and give me an rpm signal and then tune the ranges such that it works for my nitrous controller. I don't know exactly what my controller does as far as the relation between rpm and the preset fuel adjustment percentage but I could test and figure that out by plotting its output vs rpm after I have a way to do that.
So where I'm left with some questions is does anyone know exactly what the rpm lead for my nitrous controller is looking for from an electrical standpoint? In other words, I don't really know what an rpm or tach signal is in this case (it's meant for an LS1,LS2,etc btw). Secondly, I'm not as much of a geek as I wish I was - what can I use to do this whole digital I/O conversion?
If anyone has any other totally different ideas about how I could accomplish this blast away!
This is what rpm signal sources the controller uses by the way